Zusammenfassung

Thermal expansion of magnetostriction measurements on single crystalline
UPd2Al3, a very clean, strongly Pauli-limited, heavy-fermion
superconductor (T(c) congruent-to 1.82 K), have been utilized to
establish a first-order transition at T less-than-or-equal-to T
congruent-to 1.5 K and B < B(c2)(T). This is ascribed to the hitherto
unobserved formation of a nonuniform superconducting state, as predicted
theoretically in 1963.